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[petitboot] / discover / device-handler.c
1 #include <assert.h>
2 #include <stdlib.h>
3 #include <stdbool.h>
4 #include <unistd.h>
5 #include <string.h>
6 #include <errno.h>
7 #include <mntent.h>
8 #include <sys/stat.h>
9 #include <sys/wait.h>
10
11 #include <pb-config/pb-config.h>
12 #include <talloc/talloc.h>
13 #include <list/list.h>
14 #include <log/log.h>
15 #include <types/types.h>
16 #include <system/system.h>
17 #include <process/process.h>
18 #include <url/url.h>
19
20 #include "device-handler.h"
21 #include "discover-server.h"
22 #include "event.h"
23 #include "parser.h"
24 #include "resource.h"
25 #include "paths.h"
26 #include "sysinfo.h"
27 #include "boot.h"
28
29 struct device_handler {
30         struct discover_server  *server;
31         int                     dry_run;
32
33         struct discover_device  **devices;
34         unsigned int            n_devices;
35
36         struct waitset          *waitset;
37         struct waiter           *timeout_waiter;
38         bool                    autoboot_enabled;
39         unsigned int            sec_to_boot;
40
41         struct discover_boot_option *default_boot_option;
42         struct list             unresolved_boot_options;
43
44         struct boot_task        *pending_boot;
45         bool                    pending_boot_is_default;
46 };
47
48 static int mount_device(struct discover_device *dev);
49 static int umount_device(struct discover_device *dev);
50
51 void discover_context_add_boot_option(struct discover_context *ctx,
52                 struct discover_boot_option *boot_option)
53 {
54         boot_option->source = ctx->parser;
55         list_add_tail(&ctx->boot_options, &boot_option->list);
56         talloc_steal(ctx, boot_option);
57 }
58
59 /**
60  * device_handler_get_device_count - Get the count of current handler devices.
61  */
62
63 int device_handler_get_device_count(const struct device_handler *handler)
64 {
65         return handler->n_devices;
66 }
67
68 /**
69  * device_handler_get_device - Get a handler device by index.
70  */
71
72 const struct discover_device *device_handler_get_device(
73         const struct device_handler *handler, unsigned int index)
74 {
75         if (index >= handler->n_devices) {
76                 assert(0 && "bad index");
77                 return NULL;
78         }
79
80         return handler->devices[index];
81 }
82
83 struct discover_boot_option *discover_boot_option_create(
84                 struct discover_context *ctx,
85                 struct discover_device *device)
86 {
87         struct discover_boot_option *opt;
88
89         opt = talloc_zero(ctx, struct discover_boot_option);
90         opt->option = talloc_zero(opt, struct boot_option);
91         opt->device = device;
92
93         return opt;
94 }
95
96 static int device_match_uuid(struct discover_device *dev, const char *uuid)
97 {
98         return dev->uuid && !strcmp(dev->uuid, uuid);
99 }
100
101 static int device_match_label(struct discover_device *dev, const char *label)
102 {
103         return dev->label && !strcmp(dev->label, label);
104 }
105
106 static int device_match_id(struct discover_device *dev, const char *id)
107 {
108         return !strcmp(dev->device->id, id);
109 }
110
111 static int device_match_serial(struct discover_device *dev, const char *serial)
112 {
113         const char *val = discover_device_get_param(dev, "ID_SERIAL");
114         return val && !strcmp(val, serial);
115 }
116
117 static struct discover_device *device_lookup(
118                 struct device_handler *device_handler,
119                 int (match_fn)(struct discover_device *, const char *),
120                 const char *str)
121 {
122         struct discover_device *dev;
123         unsigned int i;
124
125         if (!str)
126                 return NULL;
127
128         for (i = 0; i < device_handler->n_devices; i++) {
129                 dev = device_handler->devices[i];
130
131                 if (match_fn(dev, str))
132                         return dev;
133         }
134
135         return NULL;
136 }
137
138 struct discover_device *device_lookup_by_name(struct device_handler *handler,
139                 const char *name)
140 {
141         if (!strncmp(name, "/dev/", strlen("/dev/")))
142                 name += strlen("/dev/");
143
144         return device_lookup_by_id(handler, name);
145 }
146
147 struct discover_device *device_lookup_by_uuid(
148                 struct device_handler *device_handler,
149                 const char *uuid)
150 {
151         return device_lookup(device_handler, device_match_uuid, uuid);
152 }
153
154 struct discover_device *device_lookup_by_label(
155                 struct device_handler *device_handler,
156                 const char *label)
157 {
158         return device_lookup(device_handler, device_match_label, label);
159 }
160
161 struct discover_device *device_lookup_by_id(
162                 struct device_handler *device_handler,
163                 const char *id)
164 {
165         return device_lookup(device_handler, device_match_id, id);
166 }
167
168 struct discover_device *device_lookup_by_serial(
169                 struct device_handler *device_handler,
170                 const char *serial)
171 {
172         return device_lookup(device_handler, device_match_serial, serial);
173 }
174
175 void device_handler_destroy(struct device_handler *handler)
176 {
177         talloc_free(handler);
178 }
179
180 static int destroy_device(void *arg)
181 {
182         struct discover_device *dev = arg;
183
184         umount_device(dev);
185
186         return 0;
187 }
188
189 struct discover_device *discover_device_create(struct device_handler *handler,
190                 const char *id)
191 {
192         struct discover_device *dev;
193
194         dev = device_lookup_by_id(handler, id);
195         if (dev)
196                 return dev;
197
198         dev = talloc_zero(handler, struct discover_device);
199         dev->device = talloc_zero(dev, struct device);
200         dev->device->id = talloc_strdup(dev->device, id);
201         list_init(&dev->params);
202         list_init(&dev->boot_options);
203
204         talloc_set_destructor(dev, destroy_device);
205
206         return dev;
207 }
208
209 struct discover_device_param {
210         char                    *name;
211         char                    *value;
212         struct list_item        list;
213 };
214
215 void discover_device_set_param(struct discover_device *device,
216                 const char *name, const char *value)
217 {
218         struct discover_device_param *param;
219         bool found = false;
220
221         list_for_each_entry(&device->params, param, list) {
222                 if (!strcmp(param->name, name)) {
223                         found = true;
224                         break;
225                 }
226         }
227
228         if (!found) {
229                 if (!value)
230                         return;
231                 param = talloc(device, struct discover_device_param);
232                 param->name = talloc_strdup(param, name);
233                 list_add(&device->params, &param->list);
234         } else {
235                 if (!value) {
236                         list_remove(&param->list);
237                         talloc_free(param);
238                         return;
239                 }
240                 talloc_free(param->value);
241         }
242
243         param->value = talloc_strdup(param, value);
244 }
245
246 const char *discover_device_get_param(struct discover_device *device,
247                 const char *name)
248 {
249         struct discover_device_param *param;
250
251         list_for_each_entry(&device->params, param, list) {
252                 if (!strcmp(param->name, name))
253                         return param->name;
254         }
255         return NULL;
256 }
257
258 struct device_handler *device_handler_init(struct discover_server *server,
259                 struct waitset *waitset, int dry_run)
260 {
261         struct device_handler *handler;
262
263         handler = talloc_zero(NULL, struct device_handler);
264         handler->server = server;
265         handler->waitset = waitset;
266         handler->dry_run = dry_run;
267         handler->autoboot_enabled = config_get()->autoboot_enabled;
268
269         list_init(&handler->unresolved_boot_options);
270
271         /* set up our mount point base */
272         pb_mkdir_recursive(mount_base());
273
274         parser_init();
275
276         return handler;
277 }
278
279 void device_handler_remove(struct device_handler *handler,
280                 struct discover_device *device)
281 {
282         struct discover_boot_option *opt, *tmp;
283         unsigned int i;
284
285         for (i = 0; i < handler->n_devices; i++)
286                 if (handler->devices[i] == device)
287                         break;
288
289         if (i == handler->n_devices) {
290                 talloc_free(device);
291                 return;
292         }
293
294         /* Free any unresolved options, as they're currently allocated
295          * against the handler */
296         list_for_each_entry_safe(&handler->unresolved_boot_options,
297                         opt, tmp, list) {
298                 if (opt->device != device)
299                         continue;
300                 list_remove(&opt->list);
301                 talloc_free(opt);
302         }
303
304         handler->n_devices--;
305         memmove(&handler->devices[i], &handler->devices[i + 1],
306                 (handler->n_devices - i) * sizeof(handler->devices[0]));
307         handler->devices = talloc_realloc(handler, handler->devices,
308                 struct discover_device *, handler->n_devices);
309
310         if (device->notified)
311                 discover_server_notify_device_remove(handler->server,
312                                                         device->device);
313
314         talloc_free(device);
315 }
316
317 static void boot_status(void *arg, struct boot_status *status)
318 {
319         struct device_handler *handler = arg;
320
321         discover_server_notify_boot_status(handler->server, status);
322 }
323
324 static void countdown_status(struct device_handler *handler,
325                 struct discover_boot_option *opt, unsigned int sec)
326 {
327         struct boot_status status;
328
329         status.type = BOOT_STATUS_INFO;
330         status.progress = -1;
331         status.detail = NULL;
332         status.message = talloc_asprintf(handler,
333                         "Booting %s in %u sec", opt->option->name, sec);
334
335         discover_server_notify_boot_status(handler->server, &status);
336
337         talloc_free(status.message);
338 }
339
340 static int default_timeout(void *arg)
341 {
342         struct device_handler *handler = arg;
343         struct discover_boot_option *opt;
344
345         if (!handler->default_boot_option)
346                 return 0;
347
348         if (handler->pending_boot)
349                 return 0;
350
351         opt = handler->default_boot_option;
352
353         if (handler->sec_to_boot) {
354                 countdown_status(handler, opt, handler->sec_to_boot);
355                 handler->sec_to_boot--;
356                 handler->timeout_waiter = waiter_register_timeout(
357                                                 handler->waitset, 1000,
358                                                 default_timeout, handler);
359                 return 0;
360         }
361
362         handler->timeout_waiter = NULL;
363
364         pb_log("Timeout expired, booting default option %s\n", opt->option->id);
365
366         handler->pending_boot = boot(handler, handler->default_boot_option,
367                         NULL, handler->dry_run, boot_status, handler);
368         handler->pending_boot_is_default = true;
369         return 0;
370 }
371
372 static bool priority_match(struct boot_priority *prio,
373                 struct discover_boot_option *opt)
374 {
375         return prio->type == opt->device->device->type;
376 }
377
378 static int default_option_priority(struct discover_boot_option *opt)
379 {
380         const struct config *config;
381         struct boot_priority *prio;
382         unsigned int i;
383
384         config = config_get();
385
386         for (i = 0; i < config->n_boot_priorities; i++) {
387                 prio = &config->boot_priorities[i];
388                 if (priority_match(prio, opt))
389                         break;
390         }
391
392         return i;
393 }
394
395 static void set_default(struct device_handler *handler,
396                 struct discover_boot_option *opt)
397 {
398         if (!handler->autoboot_enabled)
399                 return;
400
401         /* Resolve any conflicts: if we have a new default option, it only
402          * replaces the current if it has a higher priority. */
403         if (handler->default_boot_option) {
404                 int new_prio, cur_prio;
405
406                 new_prio = default_option_priority(opt);
407                 cur_prio = default_option_priority(
408                                         handler->default_boot_option);
409
410                 if (new_prio < cur_prio) {
411                         handler->default_boot_option = opt;
412                         /* extend the timeout a little, so the user sees some
413                          * indication of the change */
414                         handler->sec_to_boot += 2;
415                 }
416
417                 return;
418         }
419
420         handler->sec_to_boot = config_get()->autoboot_timeout_sec;
421         handler->default_boot_option = opt;
422
423         pb_log("Boot option %s set as default, timeout %u sec.\n",
424                opt->option->id, handler->sec_to_boot);
425
426         default_timeout(handler);
427 }
428
429 static bool resource_is_resolved(struct resource *res)
430 {
431         return !res || res->resolved;
432 }
433
434 /* We only use this in an assert, which will disappear if we're compiling
435  * with NDEBUG, so we need the 'used' attribute for these builds */
436 static bool __attribute__((used)) boot_option_is_resolved(
437                 struct discover_boot_option *opt)
438 {
439         return resource_is_resolved(opt->boot_image) &&
440                 resource_is_resolved(opt->initrd) &&
441                 resource_is_resolved(opt->dtb) &&
442                 resource_is_resolved(opt->icon);
443 }
444
445 static bool resource_resolve(struct resource *res, const char *name,
446                 struct discover_boot_option *opt,
447                 struct device_handler *handler)
448 {
449         struct parser *parser = opt->source;
450
451         if (resource_is_resolved(res))
452                 return true;
453
454         pb_debug("Attempting to resolve resource %s->%s with parser %s\n",
455                         opt->option->id, name, parser->name);
456         parser->resolve_resource(handler, res);
457
458         return res->resolved;
459 }
460
461 static bool boot_option_resolve(struct discover_boot_option *opt,
462                 struct device_handler *handler)
463 {
464         return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
465                 resource_resolve(opt->initrd, "initrd", opt, handler) &&
466                 resource_resolve(opt->dtb, "dtb", opt, handler) &&
467                 resource_resolve(opt->icon, "icon", opt, handler);
468 }
469
470 static void boot_option_finalise(struct device_handler *handler,
471                 struct discover_boot_option *opt)
472 {
473         assert(boot_option_is_resolved(opt));
474
475         /* check that the parsers haven't set any of the final data */
476         assert(!opt->option->boot_image_file);
477         assert(!opt->option->initrd_file);
478         assert(!opt->option->dtb_file);
479         assert(!opt->option->icon_file);
480         assert(!opt->option->device_id);
481
482         if (opt->boot_image)
483                 opt->option->boot_image_file = opt->boot_image->url->full;
484         if (opt->initrd)
485                 opt->option->initrd_file = opt->initrd->url->full;
486         if (opt->dtb)
487                 opt->option->dtb_file = opt->dtb->url->full;
488         if (opt->icon)
489                 opt->option->icon_file = opt->icon->url->full;
490
491         opt->option->device_id = opt->device->device->id;
492
493         if (opt->option->is_default)
494                 set_default(handler, opt);
495 }
496
497 static void notify_boot_option(struct device_handler *handler,
498                 struct discover_boot_option *opt)
499 {
500         struct discover_device *dev = opt->device;
501
502         if (!dev->notified)
503                 discover_server_notify_device_add(handler->server,
504                                                   opt->device->device);
505         dev->notified = true;
506         discover_server_notify_boot_option_add(handler->server, opt->option);
507 }
508
509 static void process_boot_option_queue(struct device_handler *handler)
510 {
511         struct discover_boot_option *opt, *tmp;
512
513         list_for_each_entry_safe(&handler->unresolved_boot_options,
514                         opt, tmp, list) {
515
516                 pb_debug("queue: attempting resolution for %s\n",
517                                 opt->option->id);
518
519                 if (!boot_option_resolve(opt, handler))
520                         continue;
521
522                 pb_debug("\tresolved!\n");
523
524                 list_remove(&opt->list);
525                 list_add_tail(&opt->device->boot_options, &opt->list);
526                 talloc_steal(opt->device, opt);
527                 boot_option_finalise(handler, opt);
528                 notify_boot_option(handler, opt);
529         }
530 }
531
532 struct discover_context *device_handler_discover_context_create(
533                 struct device_handler *handler,
534                 struct discover_device *device)
535 {
536         struct discover_context *ctx;
537
538         ctx = talloc_zero(handler, struct discover_context);
539         ctx->device = device;
540         list_init(&ctx->boot_options);
541
542         return ctx;
543 }
544
545 /**
546  * context_commit - Commit a temporary discovery context to the handler,
547  * and notify the clients about any new options / devices
548  */
549 void device_handler_discover_context_commit(struct device_handler *handler,
550                 struct discover_context *ctx)
551 {
552         struct discover_device *dev = ctx->device;
553         struct discover_boot_option *opt, *tmp;
554
555         if (!device_lookup_by_id(handler, dev->device->id))
556                 device_handler_add_device(handler, dev);
557
558         /* move boot options from the context to the device */
559         list_for_each_entry_safe(&ctx->boot_options, opt, tmp, list) {
560                 list_remove(&opt->list);
561
562                 if (boot_option_resolve(opt, handler)) {
563                         pb_log("boot option %s is resolved, "
564                                         "sending to clients\n",
565                                         opt->option->id);
566                         list_add_tail(&dev->boot_options, &opt->list);
567                         talloc_steal(dev, opt);
568                         boot_option_finalise(handler, opt);
569                         notify_boot_option(handler, opt);
570                 } else {
571                         if (!opt->source->resolve_resource) {
572                                 pb_log("parser %s gave us an unresolved "
573                                         "resource (%s), but no way to "
574                                         "resolve it\n",
575                                         opt->source->name, opt->option->id);
576                                 talloc_free(opt);
577                         } else {
578                                 pb_log("boot option %s is unresolved, "
579                                                 "adding to queue\n",
580                                                 opt->option->id);
581                                 list_add(&handler->unresolved_boot_options,
582                                                 &opt->list);
583                                 talloc_steal(handler, opt);
584                         }
585                 }
586         }
587 }
588
589 void device_handler_add_device(struct device_handler *handler,
590                 struct discover_device *device)
591 {
592         handler->n_devices++;
593         handler->devices = talloc_realloc(handler, handler->devices,
594                                 struct discover_device *, handler->n_devices);
595         handler->devices[handler->n_devices - 1] = device;
596
597 }
598
599 /* Start discovery on a hotplugged device. The device will be in our devices
600  * array, but has only just been initialised by the hotplug source.
601  */
602 int device_handler_discover(struct device_handler *handler,
603                 struct discover_device *dev)
604 {
605         struct discover_context *ctx;
606         int rc;
607
608         process_boot_option_queue(handler);
609
610         /* create our context */
611         ctx = device_handler_discover_context_create(handler, dev);
612
613         rc = mount_device(dev);
614         if (rc)
615                 goto out;
616
617         /* add this device to our system info */
618         system_info_register_blockdev(dev->device->id, dev->uuid,
619                         dev->mount_path);
620
621         /* run the parsers. This will populate the ctx's boot_option list. */
622         iterate_parsers(ctx);
623
624         /* add discovered stuff to the handler */
625         device_handler_discover_context_commit(handler, ctx);
626
627 out:
628         talloc_free(ctx);
629
630         return 0;
631 }
632
633 /* Incoming dhcp event */
634 int device_handler_dhcp(struct device_handler *handler,
635                 struct discover_device *dev, struct event *event)
636 {
637         struct discover_context *ctx;
638
639         /* create our context */
640         ctx = device_handler_discover_context_create(handler, dev);
641         ctx->event = event;
642
643         iterate_parsers(ctx);
644
645         device_handler_discover_context_commit(handler, ctx);
646
647         talloc_free(ctx);
648
649         return 0;
650 }
651
652 /* incoming conf event */
653 int device_handler_conf(struct device_handler *handler,
654                 struct discover_device *dev, struct pb_url *url)
655 {
656         struct discover_context *ctx;
657
658         /* create our context */
659         ctx = device_handler_discover_context_create(handler, dev);
660         ctx->conf_url = url;
661
662         iterate_parsers(ctx);
663
664         device_handler_discover_context_commit(handler, ctx);
665
666         talloc_free(ctx);
667
668         return 0;
669 }
670
671 static struct discover_boot_option *find_boot_option_by_id(
672                 struct device_handler *handler, const char *id)
673 {
674         unsigned int i;
675
676         for (i = 0; i < handler->n_devices; i++) {
677                 struct discover_device *dev = handler->devices[i];
678                 struct discover_boot_option *opt;
679
680                 list_for_each_entry(&dev->boot_options, opt, list)
681                         if (!strcmp(opt->option->id, id))
682                                 return opt;
683         }
684
685         return NULL;
686 }
687
688 void device_handler_boot(struct device_handler *handler,
689                 struct boot_command *cmd)
690 {
691         struct discover_boot_option *opt = NULL;
692
693         if (cmd->option_id && strlen(cmd->option_id))
694                 opt = find_boot_option_by_id(handler, cmd->option_id);
695
696         if (handler->pending_boot)
697                 boot_cancel(handler->pending_boot);
698         handler->pending_boot = boot(handler, opt, cmd, handler->dry_run,
699                         boot_status, handler);
700         handler->pending_boot_is_default = false;
701 }
702
703 void device_handler_cancel_default(struct device_handler *handler)
704 {
705         struct boot_status status;
706
707         if (handler->timeout_waiter)
708                 waiter_remove(handler->timeout_waiter);
709
710         handler->timeout_waiter = NULL;
711         handler->autoboot_enabled = false;
712
713         /* we only send status if we had a default boot option queued */
714         if (!handler->default_boot_option)
715                 return;
716
717         pb_log("Cancelling default boot option\n");
718
719         if (handler->pending_boot && handler->pending_boot_is_default) {
720                 boot_cancel(handler->pending_boot);
721                 handler->pending_boot = NULL;
722                 handler->pending_boot_is_default = false;
723         }
724
725         handler->default_boot_option = NULL;
726
727         status.type = BOOT_STATUS_INFO;
728         status.progress = -1;
729         status.detail = NULL;
730         status.message = "Default boot cancelled";
731
732         discover_server_notify_boot_status(handler->server, &status);
733 }
734
735 void device_handler_update_config(struct device_handler *handler,
736                 struct config *config)
737 {
738         config_set(config);
739         discover_server_notify_config(handler->server, config);
740 }
741
742 #ifndef PETITBOOT_TEST
743 static bool check_existing_mount(struct discover_device *dev)
744 {
745         struct stat devstat, mntstat;
746         struct mntent *mnt;
747         FILE *fp;
748         int rc;
749
750         rc = stat(dev->device_path, &devstat);
751         if (rc) {
752                 pb_debug("%s: stat failed: %s\n", __func__, strerror(errno));
753                 return false;
754         }
755
756         if (!S_ISBLK(devstat.st_mode)) {
757                 pb_debug("%s: %s isn't a block device?\n", __func__,
758                                 dev->device_path);
759                 return false;
760         }
761
762         fp = fopen("/proc/self/mounts", "r");
763
764         for (;;) {
765                 mnt = getmntent(fp);
766                 if (!mnt)
767                         break;
768
769                 if (!mnt->mnt_fsname || mnt->mnt_fsname[0] != '/')
770                         continue;
771
772                 rc = stat(mnt->mnt_fsname, &mntstat);
773                 if (rc)
774                         continue;
775
776                 if (!S_ISBLK(mntstat.st_mode))
777                         continue;
778
779                 if (mntstat.st_rdev == devstat.st_rdev) {
780                         dev->mount_path = talloc_strdup(dev, mnt->mnt_dir);
781                         dev->mounted_rw = !!hasmntopt(mnt, "rw");
782                         dev->mounted = true;
783                         dev->unmount = false;
784
785                         pb_debug("%s: %s is already mounted (r%c) at %s\n",
786                                         __func__, dev->device_path,
787                                         dev->mounted_rw ? 'w' : 'o',
788                                         mnt->mnt_dir);
789                         break;
790                 }
791         }
792
793         fclose(fp);
794
795         return mnt != NULL;
796 }
797
798 static int mount_device(struct discover_device *dev)
799 {
800         int rc;
801
802         if (!dev->device_path)
803                 return -1;
804
805         if (dev->mounted)
806                 return 0;
807
808         if (check_existing_mount(dev))
809                 return 0;
810
811         dev->mount_path = join_paths(dev, mount_base(),
812                                         dev->device_path);
813
814         if (pb_mkdir_recursive(dev->mount_path)) {
815                 pb_log("couldn't create mount directory %s: %s\n",
816                                 dev->mount_path, strerror(errno));
817                 goto err_free;
818         }
819
820         rc = process_run_simple(dev, pb_system_apps.mount,
821                         dev->device_path, dev->mount_path,
822                         "-o", "ro", NULL);
823         if (!rc) {
824                 dev->mounted = true;
825                 dev->mounted_rw = false;
826                 dev->unmount = true;
827                 return 0;
828         }
829
830         /* Retry mount without ro option. */
831         rc = process_run_simple(dev, pb_system_apps.mount,
832                         dev->device_path, dev->mount_path, NULL);
833
834         if (!rc) {
835                 dev->mounted = true;
836                 dev->mounted_rw = true;
837                 dev->unmount = true;
838                 return 0;
839         }
840
841         pb_rmdir_recursive(mount_base(), dev->mount_path);
842 err_free:
843         talloc_free(dev->mount_path);
844         dev->mount_path = NULL;
845         return -1;
846 }
847
848 static int umount_device(struct discover_device *dev)
849 {
850         int status;
851
852         if (!dev->mounted || !dev->unmount)
853                 return 0;
854
855         status = process_run_simple(dev, pb_system_apps.umount,
856                         dev->mount_path, NULL);
857
858         if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
859                 return -1;
860
861         dev->mounted = false;
862
863         pb_rmdir_recursive(mount_base(), dev->mount_path);
864
865         talloc_free(dev->mount_path);
866         dev->mount_path = NULL;
867
868         return 0;
869 }
870
871 int device_request_write(struct discover_device *dev, bool *release)
872 {
873         int rc;
874
875         *release = false;
876
877         if (!dev->mounted)
878                 return -1;
879
880         if (dev->mounted_rw)
881                 return 0;
882
883         rc = process_run_simple(dev, pb_system_apps.mount, dev->mount_path,
884                         "-o", "remount,rw", NULL);
885         if (rc)
886                 return -1;
887
888         dev->mounted_rw = true;
889         *release = true;
890         return 0;
891 }
892
893 void device_release_write(struct discover_device *dev, bool release)
894 {
895         if (!release)
896                 return;
897
898         process_run_simple(dev, pb_system_apps.mount, dev->mount_path,
899                         "-o", "remount,ro", NULL);
900         dev->mounted_rw = false;
901 }
902
903 #else
904
905 static int umount_device(struct discover_device *dev __attribute__((unused)))
906 {
907         return 0;
908 }
909
910 static int __attribute__((unused)) mount_device(
911                 struct discover_device *dev __attribute__((unused)))
912 {
913         return 0;
914 }
915
916 int device_request_write(struct discover_device *dev __attribute__((unused)),
917                 bool *release)
918 {
919         *release = true;
920         return 0;
921 }
922
923 void device_release_write(struct discover_device *dev __attribute__((unused)),
924         bool release __attribute__((unused)))
925 {
926 }
927
928 #endif
929